JP2019049275A - Hydraulic control device for automatic transmission - Google Patents

Abstract

To provide a hydraulic control device for an automatic transmission capable of improving fuel economy by reducing the load of an oil pump.SOLUTION: The hydraulic control device includes a hydraulic pressure supply mechanism (46) having hydraulic pressure supply sources (46a1, 46a2) for supplying operating oil and flow amount estimation means (92) for estimating an estimated supply flow amount (Qs) as the flow amount of the operating oil supplied by the hydraulic pressure supply source (46a1), for supplying a hydraulic pressure to the automatic transmission, and control means (91) for controlling the hydraulic pressure supply mechanism (46). The control means (91) sets a target hydraulic pressure at a predetermined position to be a hydraulic pressure (Phh) higher than a regularly set hydraulic pressure when performing correction control of the estimated supply flow amount (Qs), while acquiring a detection pressure (Ps) at the predetermined position. Then, it corrects the estimated supply flow amount (Qs) on the basis of the detection pressure (Ps).SELECTED DRAWING: Figure 5

Description

  The present invention relates to a hydraulic control device for an automatic transmission, and more particularly to a hydraulic control device for an automatic transmission capable of switching the flow rate of hydraulic fluid to a hydraulic circuit in at least two stages.

  Conventionally, there is a hydraulic control device for an automatic transmission that reduces the load of an oil pump driven by an internal combustion engine (engine) to improve fuel economy (fuel consumption) (see, for example, Patent Document 1). In patent document 1, the pressure (line pressure) which supplies hydraulic fluid to the main hydraulic circuit which has a friction fastening element has a line pressure control valve which can be switched to two steps of low pressure and high pressure. Control to be more. When the line pressure is low, the load on the oil pump that supplies the hydraulic oil to the line pressure control valve is reduced as compared to when the line pressure is high. Then, the load on the engine that drives the oil pump is also reduced, and the fuel efficiency is improved.

  Here, in order to output the necessary line pressure in the main hydraulic circuit, the flow rate of the hydraulic oil supplied from the oil pump to the main hydraulic circuit must be sufficient. However, constantly supplying more hydraulic oil than necessary to the high pressure main hydraulic circuit increases the load on the oil pump. For this reason, conventionally, the hydraulic oil supplied from the oil pump to two hydraulic circuits including a clutch and the like and a high-pressure main hydraulic circuit and a low-pressure sub-hydraulic circuit which is constituted by a lubricating system and the like. The flow rate is estimated, and if it is determined that the flow rate more than necessary is supplied to the main hydraulic circuit, switching is made to flow a part of the hydraulic oil discharged from the oil pump to the sub hydraulic circuit. As a result, the flow rate switching control is performed to reduce the flow rate from the oil pump to the high pressure main hydraulic circuit and reduce the load on the oil pump. The switching of the flow rate switching control is performed based on the estimated flow rate of the hydraulic oil from the oil pump to the main hydraulic circuit, and the estimated flow rate is calculated at the time of operation of the oil pump.

  However, in calculating the estimated flow rate, conventionally, in consideration of individual differences and durability deterioration of the oil pump, the estimated flow rate of the hydraulic oil discharged from the oil pump is determined based on the oil pump having a relatively low discharge capacity. Was. In this case, even in the case of an oil pump having a high discharge capacity, the flow switching control must be performed using an estimated flow rate of the oil pump having a low discharge capacity. Assuming an oil pump with a low discharge capacity, if the supply flow rate of the oil pump is estimated, more flow will be supplied to the high pressure main hydraulic circuit than the actually required supply flow. As a result, the load on the oil pump may be increased, and the fuel efficiency may be degraded.

Japanese Patent Application Laid-Open No. 2002-089679

  The present invention has been made in view of the above-described point, and an object thereof is to provide a hydraulic control device of an automatic transmission which can reduce the load of the oil pump and improve the fuel consumption.

  In order to solve the above problems, the hydraulic control device for an automatic transmission according to the present invention comprises an oil pressure supply mechanism (46) for supplying oil pressure to an automatic transmission that transmits power at a predetermined gear ratio; 46) a control means (91) for controlling the hydraulic pressure of the automatic transmission, the hydraulic supply mechanism (46) comprising a main hydraulic circuit (47) requiring a relatively high hydraulic pressure , A sub hydraulic circuit (48) requiring relatively low hydraulic pressure, and a hydraulic supply source (46a1) driven by the internal combustion engine (10) to supply hydraulic fluid to the main hydraulic circuit (47) and the sub hydraulic circuit (48) , 46a2), the first state (lubrication mode) in which the flow rate supplied from the hydraulic pressure supply source (46a1, 46a2) to the main hydraulic circuit (47) is relatively small, and the main hydraulic pressure from the hydraulic pressure supply source (46a1, 46a2) circuit 47) detects the hydraulic pressure at a predetermined position of the main hydraulic circuit (47), and the flow rate adjusting means (46g) which can be switched to at least two stages of the second state (high pressure mode) in which the flow rate supplied to 47) is relatively high. Hydraulic pressure detection means (82a), target hydraulic pressure setting means (94) for setting a target hydraulic pressure at a predetermined position, and estimated supply flow rate (Qs) which is the flow rate of hydraulic oil supplied by the hydraulic pressure supply source (46a1) in the first state Flow rate estimation means (92) for estimating the), and the control means (91) performs correction control for correcting the estimated supply flow rate (Qs), the target oil pressure being higher than that normally set. A detection pressure (Ps) at a predetermined position when it is set to a predetermined hydraulic pressure (Phh) is acquired, and the estimated supply flow rate (Qs) is corrected based on the detection pressure (Ps).

  As described above, when the control means performs correction control of the estimated supply flow rate, the main hydraulic pressure is set by setting the target hydraulic pressure at the predetermined position to a predetermined hydraulic pressure higher than the hydraulic pressure normally set and acquiring the detected pressure at the predetermined position. The maximum hydraulic pressure that can be obtained at a predetermined position of the circuit can be grasped. Here, if the detected pressure at the predetermined position obtained in the correction control is large, it is determined that the flow rate of the hydraulic oil supplied from the hydraulic pressure supply source has a margin, and correction is performed to increase the estimated supply flow rate. On the other hand, if the detected pressure at the predetermined position obtained in the correction control is small, it is determined that the flow rate of the hydraulic oil supplied from the hydraulic pressure supply source has no margin, and correction is performed to reduce the estimated supply flow rate. Thus, by correcting the estimated supply flow rate of the hydraulic oil supplied from the hydraulic pressure source in the first state, a more accurate flow rate can be estimated. Then, if the flow control means switches the first state and the second state based on the value of the estimated supply flow rate more accurately, the first state can be increased as compared with the case where the correction control is not performed, The load on the supply source and the internal combustion engine that drives it can be reduced. As a result, fuel consumption can be improved.

  Further, in the hydraulic control device of the automatic transmission, the control means (91) may switch the flow rate adjusting means (46g) to be in the first state (lubrication mode) when performing the correction control.

  As described above, when performing the correction control, the control means causes the flow rate adjusting means to be in the first state, thereby grasping the detected pressure when the flow rate supplied from the hydraulic pressure supply source to the main hydraulic circuit is relatively small. Can. Then, it is possible to grasp how much the flow rate margin of the hydraulic oil supplied from the hydraulic pressure supply source in the first state is, and when estimating the estimated supply flow rate, it is possible to estimate the flow rate more accurately.

  Further, in the hydraulic control device of the automatic transmission, the hydraulic pressure supply sources (46a1, 46a2) are composed of a first oil pump (46a1) and a second oil pump (46a2), and the control means (91) is In one state (lubrication mode), hydraulic oil is supplied from the first oil pump (46a1) only to the main hydraulic circuit (47), and in the second state (high pressure mode), the first oil pump (46a1) and the second oil The flow rate adjusting means (46g) may be controlled to supply the hydraulic fluid from the pump (46a2) to the main hydraulic circuit (47).

  Thus, assuming that the hydraulic pressure supply source comprises the first oil pump and the second oil pump, and in the first state that the hydraulic oil is supplied to the main hydraulic circuit from only the first oil pump, it is used in the first state The characteristics of the first oil pump can be grasped. Further, in the first state, since the second oil pump does not supply hydraulic oil to the high pressure main hydraulic circuit, the load on the second oil pump and the internal combustion engine that drives the second oil pump can be reduced.

  Further, in the hydraulic control device for an automatic transmission, the automatic transmission is mounted on a vehicle (1), and a rotational speed sensor for detecting the rotational speed of the drive wheel (12) on the drive wheel (12) of the vehicle (1) (81) may be disposed, and the control means (91) may perform correction control when it is determined that the rotational speed of the rotational speed sensor (81) is zero.

  Further, in the hydraulic control device of the automatic transmission, the automatic transmission includes shift switching means (44) for the driver to indicate a shift range, and the control means (91) is a shift switching means (44). When the parking range of is selected, the correction control may be performed.

  As described above, if the correction control is performed after confirming that the rotation speed of the drive wheel is 0 or that the instruction value of the shift switching means is in the parking range, the correction control is performed when the vehicle is stopped. For this reason, even if the driver does not give an instruction in particular, it is possible to correct the estimated supply flow rate of hydraulic oil at a timing at which there is no trouble in traveling.

  The reference numerals in the above parentheses indicate the reference numerals of the corresponding components of the embodiments described later as an example of the present invention.

  According to the hydraulic control device for an automatic transmission according to the present invention, the load on the oil pump can be reduced to improve the fuel consumption.

1 is a view showing an example of the overall configuration of a vehicle provided with a hydraulic control device for an automatic transmission according to the present embodiment. It is a hydraulic circuit diagram of a hydraulic pressure supply mechanism. It is a block diagram of a hydraulic control system. It is a flowchart regarding the determination method of presumed flow volume. It is a flowchart regarding correction | amendment control of presumed supply flow volume. It is a figure which shows the change of the target oil pressure of the predetermined position in correction | amendment control, and a detection pressure.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a view showing an example of the overall configuration of a vehicle 1 provided with a hydraulic control device for an automatic transmission according to the present embodiment. An automatic transmission is mounted on a vehicle 1 shown in the figure. More specifically, in the vehicle 1, an engine 10 (internal combustion engine) as a drive source, a torque converter 24, and a continuously variable transmission 26 (CVT: Continuous) that shifts and outputs rotation by the driving force of the engine 10 A variable transmission) and a forward and reverse switching device 28 are provided. The forward / reverse switching device 28 includes a forward clutch 28 a provided to connect and disconnect the transmission of the driving force of the engine 10 to the continuously variable transmission 26. The vehicle 1 also includes an engine controller 66 and a shift controller 90 which are control devices for controlling the engine 10, the continuously variable transmission 26, and the forward / reverse switching device 28 described above.

  The throttle valve (not shown) disposed in the intake system of the engine 10 is mechanically disconnected from the accelerator pedal disposed on the floor surface of the driver's seat of the vehicle and is a DBW mechanism 16 comprising an actuator such as an electric motor It is connected to the (Drive By Wire mechanism) and is opened and closed by the DBW mechanism 16.

  The intake air metered by the throttle valve flows through the intake manifold (not shown) and mixes with the fuel injected from the injector 20 near the intake port of each cylinder to form an air-fuel mixture, and the intake valve (see FIG. When the valve is opened, it flows into the combustion chamber (not shown) of the cylinder. In the combustion chamber, the air-fuel mixture is ignited and burned to drive the piston to rotate the crankshaft 22, and then is discharged to the outside of the engine 10 as exhaust gas.

  The crankshaft 22 of the engine 10 is connected to the pump / impeller 24a of the torque converter 24, while the turbine runner 24b disposed opposite to it and receiving the fluid (hydraulic fluid) is connected to the main shaft MS (input shaft) Ru. The rotation of the crankshaft 22 is thereby input to the torque converter 24. The torque converter 24 also has a lockup clutch 24c.

  Further, the rotation of the crankshaft 22 is input to the continuously variable transmission 26 via the torque converter 24. The continuously variable transmission 26 includes a drive pulley 26a disposed on the main shaft MS, more precisely on its outer peripheral shaft, and a counter shaft CS (output shaft) parallel to the main shaft MS, more precisely on the counter shaft CS. The driven pulley 26b is disposed on the outer peripheral side shaft, and an endless flexible member such as a metal belt 26c is wound around the driven pulley 26b.

  The drive pulley 26a is fixed to the fixed pulley half 26a1 which is arranged relatively immovably relative to the outer peripheral shaft of the main shaft MS and immovable in the axial direction and to the outer peripheral side shaft of the main shaft MS. The movable pulley half 26a2 is movable relative to the other in the axial direction. The driven pulley 26b can not rotate relative to the outer peripheral shaft of the countershaft CS and can not move in the axial direction. The driven pulley 26b can not rotate relative to the countershaft CS and can not rotate relative to the fixed pulley half 26b1. And a movable pulley half 26b2 movable relative to each other.

  The continuously variable transmission 26 is connected to the engine 10 via the forward and reverse switching device 28. The forward / reverse switching device 28 includes a forward clutch 28a that enables the vehicle to travel in the forward direction, a reverse brake clutch 28b that enables the vehicle to travel in the reverse direction, and a planetary gear mechanism 28c disposed therebetween. The continuously variable transmission 26 is connected to the engine 10 via a forward clutch 28 a.

  In the planetary gear mechanism 28c, the sun gear 28c1 is fixed to the main shaft MS, and the ring gear 28c2 is fixed to the fixed pulley half 26a1 of the drive pulley 26a via the forward clutch 28a. A pinion 28c3 is disposed between the sun gear 28c1 and the ring gear 28c2. The pinion 28c3 meshes with the sun gear 28c1 and is integrally formed with the carrier 28c4. The carrier 28c4 is locked (locked) by the reverse brake clutch 28b when it is actuated.

  The rotation of the countershaft CS is transmitted from the secondary shaft SS (intermediate shaft) to the drive wheel 12 via a gear. That is, the rotation of the countershaft CS is transmitted to the secondary shaft SS via the gears 30a and 30b, and the rotation is transmitted from the differential 32 to the drive shaft 34 via the gear 30c, and finally the left and right drive wheels 12 (right Is shown only).

  A disk brake 36 is disposed in the vicinity of the drive wheel 12 (front wheel) and a driven wheel (not shown) (rear wheel). A brake pedal 40 and an accelerator pedal 56 are disposed on the floor of the driver's seat of the vehicle. A brake switch 40 a is provided near the brake pedal 40. The brake switch 40 a outputs an on signal in response to the driver's operation of the brake pedal 40. Further, in the vicinity of the accelerator pedal 56, an accelerator opening sensor 56a is provided. The accelerator opening degree sensor 56a outputs a signal proportional to the accelerator opening degree corresponding to the driver's accelerator pedal operation amount.

  In the forward / reverse switching device 28, the driver operates the range selector 44 (shift switching means) provided on the driver's seat of the vehicle to switch between the forward clutch 28a and the reverse brake clutch 28b, for example, P (parking range), R, N , D, etc., by selecting one of the ranges (shift range). Range selection by the driver's operation of the range selector 44 is transmitted to the manual valve of the hydraulic pressure supply mechanism 46. Near the range selector 44, a range selector switch 44a is provided. The range selector switch 44a outputs a signal corresponding to the range of P, R, N, D, etc. selected by the driver.

  When, for example, the D, S, or L range is selected via the range selector 44, the spool of the manual valve moves accordingly, and hydraulic fluid (hydraulic pressure) is discharged from the piston chamber of the reverse brake clutch 28b. The hydraulic pressure is supplied to the piston chamber of the forward clutch 28a, and the forward clutch 28a is engaged.

  When the forward clutch 28a is engaged, all the gears rotate integrally with the main shaft MS, and the drive pulley 26a is driven in the same direction (forward direction) as the main shaft MS. Thus, the vehicle travels in the forward direction.

  When the R range is selected, hydraulic oil is discharged from the piston chamber of the forward clutch 28a, while hydraulic pressure is supplied to the piston chamber of the reverse brake clutch 28b to operate the reverse brake clutch 28b.

  When the P or N range is selected, hydraulic oil is discharged from both piston chambers, the forward clutch 28a and the reverse brake clutch 28b are both released, and the power transmission through the forward / reverse switching device 28 is interrupted. Power transmission between 10 and the drive pulley 26 a of the continuously variable transmission 26 is interrupted.

  A crank angle sensor 50 is provided at an appropriate position such as near a cam shaft (not shown) of the engine 10. The crank angle sensor 50 outputs a signal indicating the engine speed NE at each predetermined crank angle position of the piston. An absolute pressure sensor 52 is provided at an appropriate position downstream of the throttle valve in the intake system. The absolute pressure sensor 52 outputs a signal proportional to the intake pipe absolute pressure (engine load) PBA. The actuator of the DBW mechanism 16 is provided with a throttle opening degree sensor 54.

  The output of the crank angle sensor 50 or the like is sent to the engine controller 66. The engine controller 66 includes a microcomputer, determines the target throttle opening degree based on the sensor output to control the operation of the DBW mechanism 16, and determines the fuel injection amount to drive the injector 20.

  An NT sensor 70 is provided on the main shaft MS. The NT sensor 70 outputs a pulse signal indicating the rotational speed of the turbine runner 24b, specifically, the rotational speed NT of the main shaft MS, more specifically, the input shaft rotational speed of the forward clutch 28a.

  An NDR sensor 72 is provided in the vicinity of the drive pulley 26 a of the continuously variable transmission 26. The NDR sensor 72 outputs a pulse signal according to the rotation speed NDR of the drive pulley 26a, in other words, the output shaft rotation speed of the forward clutch 28a.

  An NDN sensor 74 is provided in the vicinity of the driven pulley 26b. The NDN sensor 74 outputs a pulse signal indicating the number of revolutions NDN of the driven pulley 26b, that is, the number of revolutions of the counter shaft CS. A V sensor 76 is provided near the gear 30 b of the secondary shaft SS. The V sensor 76 outputs a pulse signal indicating the vehicle speed V through the rotation speed of the secondary shaft SS.

  The oil pressure supply mechanism 46 is provided with an oil pressure sensor 82 disposed in a predetermined oil passage and measuring an oil pressure, and an oil temperature sensor 84 measuring an oil temperature. In addition, a wheel speed sensor 81 (rotational speed sensor) is provided on the drive shaft 34 that rotates the drive wheel 12.

  The outputs of the various sensors described above, including the outputs of other sensors not shown, are sent to the shift controller 90. The shift controller 90 also includes a microcomputer including a CPU, a ROM, a RAM, an I / O, and the like, and is configured to be communicable with the engine controller 66.

  FIG. 2 is a hydraulic circuit diagram of the hydraulic pressure supply mechanism 46. As shown in FIG. The hydraulic pressure supply mechanism 46 of the present embodiment is composed of a main hydraulic circuit 47 and a sub hydraulic circuit 48. The main hydraulic circuit 47 includes a PH control valve 46c described later, and is a hydraulic circuit for controlling the continuously variable transmission 26, the forward / reverse switching device 28, and the torque converter 24. The sub hydraulic circuit 48 is a hydraulic circuit having a lubrication system 46 j described later. Since the main hydraulic circuit 47 has many components requiring hydraulic control, the hydraulic pressure of the main hydraulic circuit 47 is relatively high. On the other hand, the hydraulic pressure of the sub hydraulic circuit 48 is a relatively low hydraulic pressure.

  The hydraulic pressure supply mechanism 46 is provided with a first oil pump 46a1 and a second oil pump 46a2. The rotor of the first oil pump 46a1 and the rotor of the second oil pump 46a2 are disposed coaxially with the rotation shaft of the engine 10. Therefore, the first oil pump 46a1 and the second oil pump 46a2 are driven by the rotation of the engine 10.

  The first oil pump 46a1 pumps up the hydraulic oil stored in the reservoir 46b below the CVT case (not shown), and pumps the hydraulic oil to an oil passage 46d connected to the PH control valve 46c. The second oil pump 46a2 pumps up the hydraulic oil from the reservoir 46b, and pumps the hydraulic oil to an oil passage 46e connected to the pump switching valve 46g (flow rate adjusting means).

  A PH control valve 46c is connected to the oil passage 46d. The PH control valve 46c regulates the discharge pressure (original pressure) of the first oil pump 46a1 and the discharge pressure applied from the second oil pump 46a2 as necessary to the PH pressure (line pressure) to obtain an oil passage Output to 46k.

  The pump switching valve 46g has a spring 46g1, which is a biasing member, at one end of the spool of the pump switching valve 46g. The pump switching valve 46g is biased to the left in the figure by a spring 46g1.

  The output of the pump switching valve 46g is connected to the oil passage 46f connected to the oil passage 46d on the one hand, and to the oil passage 46h on the other hand, and is connected to the lubrication system 46j from there via the lubrication control valve 46i. Ru. The lubrication system 46j is a generic term for components or members that require lubrication.

  Then, in the hydraulic pressure supply mechanism 46, the mode (state) can be switched in at least two stages of the lubrication mode (first state) and the high-pressure mode (second state) by switching the pump switching valve 46g. The lubrication mode is a mode in which the flow rate of the hydraulic fluid supplied to the main hydraulic circuit 47 is relatively small, and the high pressure mode is a mode in which the flow rate of the hydraulic fluid supplied to the main hydraulic circuit 47 is relatively large.

  The switching operation of the pump switching valve 46g at the time of switching between the lubrication mode and the high pressure mode will be described. In the lubrication mode, the pump switching valve 46g supplies the hydraulic oil supplied from the second oil pump 46a2 to the oil path 46h on the lubrication side. Therefore, the hydraulic oil is supplied to the PH control valve 46c only from the first oil pump 46a1. On the other hand, in the high pressure mode, the pump switching valve 46g supplies the hydraulic oil supplied from the second oil pump 46a2 to the oil passage 46f on the high pressure side. Therefore, the hydraulic oil is supplied to the PH control valve 46c from the first oil pump 46a1 and the second oil pump 46a2. As described above, the pump switching valve 46g switches the oil passage supplying the hydraulic oil, whereby the flow rate of the hydraulic oil supplied to the PH control valve 46c is relatively small compared to the first flow rate Q1. It switches to one with the flow rate Q2.

  The oil passage 46k is connected to the piston chamber 26a21 of the movable pulley half 26a2 of the drive pulley 26a via the DR control valve 46m1. The oil passage 46k is connected to the piston chamber 26b21 of the movable pulley half 26b2 of the driven pulley 26b via the DN control valve 46m2.

  A DN pulley pressure sensor 82a (hydraulic pressure detecting means) is disposed between the piston chamber 26b21 of the movable pulley half 26b2 and the DN control valve 46m2. Thus, the side pressure of the movable pulley half 26b2 of the driven pulley 26b can be measured.

  The first linear solenoid valve 46m11 and the second linear solenoid valve 46m21 are pilot pressure adjusted with the later-described CR pressure sent from the oil passage 46p as an original pressure, one end of the spool of the DR control valve 46m1 and the DN control valve 46m2 Supply to

  The DR control valve 46m1 is adjusted with the PH pressure as the original pressure, and is supplied to the piston chamber 26a21 of the movable pulley half 26a2 of the drive pulley 26a. The DN control valve 46m2 is adjusted with the PH pressure as the base pressure, and is supplied to the piston chamber 26b21 of the movable pulley half 26b2 of the driven pulley 26b. Thus, the pulley side pressure and the driven pulley side pressure are generated.

  As a result, in the continuously variable transmission 26, pulley side pressure for moving the movable pulley half 26a2 and the movable pulley half 26b2 in the axial direction is generated, and the pulley width of the drive pulley 26a and the driven pulley 26b changes. As a result, the winding radius of the belt 26c is changed, and the transmission gear ratio for transmitting the output of the engine 10 to the drive wheels 12 is continuously changed.

  The oil passage 46k is connected to the CR valve 46o via an oil passage 46n on the other hand. The CR valve 46 o reduces the PH pressure adjusted by the PH control valve 46 c to a CR pressure (clutch reducing pressure (control pressure)) and discharges it to the oil passage 46 p. The output pressure (CR pressure) of the CR valve 46o discharged to the oil passage 46p is input to the third linear solenoid valve 46q, where it is adjusted to an appropriate hydraulic pressure according to the excitation of the solenoid.

  The hydraulic pressure adjusted by the third linear solenoid valve 46q is input from the input port 46r1 of the backup valve 46r provided for backup at the time of failure, and is output from the output port 46r2. Then, it is connected to the piston chamber 28a1 of the forward clutch 28a of the forward / reverse switching device 28 or the piston chamber 28b1 of the reverse brake clutch 28b via the manual valve 46s.

  The manual valve 46s adjusts the output pressure adjusted by the third linear solenoid valve 46q according to the output signal of the range selector 44 operated by the driver, to the piston chamber 28a1 of the forward clutch 28a or the piston chamber of the reverse brake clutch 28b. Connect to 28b1. This enables forward or reverse travel of the vehicle.

  Further, the discharge pressure of the PH control valve 46c is sent as the torque converter source pressure to the TC control valve 46u via the oil passage 46t. The output pressure of the TC control valve 46u is sent to the piston chamber of the lockup clutch 24c of the torque converter 24, and the discharge pressure is sent to the lubricating system 46j.

  The structure of the hydraulic control device will be described with reference to FIG. FIG. 3 is a block diagram of a hydraulic control device. The hydraulic control device of the present embodiment is configured such that the shift controller 90 includes at least a control unit 91 (control means), a flow amount estimation means 92, and a target hydraulic pressure setting means 94. The flow rate estimation unit 92 corrects the estimated supply flow rate Qs and the estimated consumption flow rate Qc by the storage unit 92a storing information such as an estimated supply flow rate Qs and a map for obtaining the estimated consumption flow rate Qc described later. And the correction unit 92b of FIG.

  The control unit 91 supplies hydraulic pressure based on output signals from various sensors such as the range selector switch 44 a of the range selector 44 and the wheel speed sensor 81 and the results obtained by the flow rate estimation unit 92 and the target hydraulic pressure setting unit 94. The pump switching valve 46g of the mechanism 46 is controlled. Specifically, by switching the pump switching valve 46g, the flow rate supplied to the PH control valve 46c is adjusted to the first flow rate Q1 or the second flow rate Q2.

  The flow rate estimation means 92 includes the rotational speed of the first oil pump 46a1 connected directly to the engine 10, the detected values of the oil pressure sensor 82 including the DN pulley pressure sensor 82a, the oil temperature sensor 84, etc., and the flow rate stored in the storage unit 92a. Estimate the flow rate of hydraulic oil based on the map of The estimated flow rate of the hydraulic oil estimated by the flow rate estimation means 92 includes an estimated supply flow rate Qs supplied from the first oil pump 46a1 and an estimated consumption flow rate Qc consumed by the main hydraulic circuit 47.

  The estimated supply flow rate Qs in the present embodiment is obtained by estimating the flow rate of the hydraulic oil supplied from the first oil pump 46a1 of the two oil pumps. For example, even when one oil pump constitutes a hydraulic pressure supply source, when the hydraulic oil is supplied from the oil pump to the main hydraulic circuit 47, the supply flow rate is relatively smaller than the relatively small first flow rate. The first flow rate may be estimated when switching is possible in two stages with a large number of second flow rates.

  The map stored in the storage unit 92a includes, for example, the oil temperature of the working oil, the number of rotations of the oil pump, the line pressure, etc., and the map serving as the reference of the supply flow rate There is a map that is configured and used as a reference for the consumption flow rate of hydraulic oil, a map that is used as a reference for the consumption flow rate of hydraulic oil consumed by the continuously variable transmission 26, and the like. The specific configuration of the map is not limited to this.

  The correction unit 92b corrects the value of the map based on the result of balance calculation of the flow rate performed by comparing the estimated supply flow rate Qs and the estimated consumption flow rate Qc performed by the control unit 91. For example, when it is determined that the estimated supply flow rate Qs0 obtained from the reference map Ms0 serving as a reference on the supply side is different from the actual supply flow rate, the value obtained from the map Ms0 is multiplied by a predetermined correction coefficient C1 to obtain C1 × Ms0 The obtained map Ms1 is used as a reference map to obtain the next estimated supply flow rate Qs. Similarly, when it is determined that the estimated consumption flow rate Qc0 obtained from the map Mc0 serving as a certain reference on the consumption side is different from the actual consumption flow rate, the value obtained from the map Mc0 serving as the reference for the consumption side has a predetermined correction coefficient C2. And the map Mc1 obtained from C2 × Mc0 is used as a reference map to obtain the next estimated consumption flow rate Qc. The correction method does not necessarily have to be performed by multiplying the value obtained from the map by the correction coefficient, and may be performed by adding or subtracting a predetermined correction value to the value obtained from the map. Further, the correction may be performed by adding or subtracting a predetermined correction value to a value obtained by multiplying the correction coefficient with a value obtained from a part of the map.

  The target hydraulic pressure setting unit 94 sets a target hydraulic pressure when the control unit 91 controls the hydraulic pressure supply mechanism 46. The setting of the target hydraulic pressure Pt by the target hydraulic pressure setting means 94 is performed by a command from the control unit 91. However, the present invention is not limited to this, and the target hydraulic pressure Pt may be set based on the value obtained from the flow rate estimating means 92.

  With this configuration, when the target hydraulic pressure setting unit 94 sets the target hydraulic pressure Pt in a normal state, the target hydraulic pressure setting unit 94 sets the hydraulic pressure of each member of the hydraulic pressure supply mechanism 46. For example, the piston chamber of the lockup clutch 24c, the piston chamber 28a1 of the forward clutch 28a, the piston chamber 28b1 of the reverse brake clutch 28b, the piston chamber 26b21 of the driven pulley 26b, and the piston chamber 26a21 of the drive pulley 26a is there.

  When the target hydraulic pressure setting unit 94 sets the hydraulic pressure, the target hydraulic pressure setting unit 94 acquires information on the traveling state of the vehicle, information on the transmission ratio, and the like from various sensors. Then, based on these pieces of information, the target hydraulic pressure setting means 94 calculates the necessary pressure at the predetermined position.

  Further, the target hydraulic pressure setting means 94 of the present embodiment, when performing the correction control of the estimated supply flow rate Qs, sets the predetermined hydraulic pressure Phh which is a hydraulic pressure which is particularly higher than the hydraulic pressure normally set as the target hydraulic pressure Pt at the predetermined position. It can be set. In the present embodiment, as the predetermined position used for the correction control of the estimated supply flow rate, a case where the piston chamber 26b21 of the driven pulley 26b is used will be described as an example. That is, when performing correction control to correct the estimated supply flow rate Qs, a predetermined hydraulic pressure Phh, which is a hydraulic pressure higher than the target hydraulic pressure Pt at a normal position, for example, the hydraulic pressure of the piston chamber 26b21 of the driven pulley 26b It can be set to

  4, the determination of the flow rate supplied to the PH control valve 46c based on the determination of the estimated flow rate (estimated supply flow rate Qs and estimated consumption flow rate Qc) by the controller 91 and the estimated flow rate, and the pump switching valve 46g The switching timing will be described. FIG. 4 is a flowchart regarding a method of determining the estimated flow rate.

  As shown in FIG. 4, first, the control unit 91 determines the estimated supply flow rate Qs and the estimated consumption flow rate Qc based on the values obtained from the various sensors described above and the map stored in the storage unit 92a of the flow rate estimation means 92. Calculate (step S1).

  Then, the control unit 91 compares the estimated supply flow rate Qs with the estimated consumption flow rate Qc (step S2). Here, when the estimated supply flow rate Qs exceeds the estimated consumption flow rate Qc, it is determined that the flow rate supplied to the main hydraulic circuit 47 may be a relatively small first flow rate Q1 (step S3). On the other hand, when the estimated supply flow rate Qs does not exceed the estimated consumption flow rate Qc, it is determined that the flow rate supplied to the main hydraulic circuit 47 should supply a relatively large second flow rate Q2 (step S4).

  Next, the control unit 91 determines whether it is necessary to switch the pump switching valve 46g (step S5). Specifically, the flow rate supplied to the PH control valve 46c changes from the first flow rate Q1 to the second flow rate Q2, or the flow rate supplied to the PH control valve 46c changes from the second flow rate Q2 to the first flow rate Q1. Is this.

  Here, when it is necessary to switch the flow rate, the controller 91 switches the pump switching valve 46g (step S6). On the other hand, when it is not necessary to switch the flow rate, the controller 91 does not switch the pump switching valve 46g.

  The correction of the estimated supply flow rate Qs will be described with reference to FIG. FIG. 5 is a flowchart regarding correction control of the estimated supply flow rate Qs.

  The correction control of the estimated supply flow rate Qs in the present embodiment is performed while the vehicle 1 is stopped. Therefore, the control unit 91 determines whether the number of revolutions acquired from the wheel speed sensor 81 is zero (step S11). Further, in order to more reliably detect that the driver instructs the vehicle 1 to stop, the control unit 91 receives a signal from the range selector switch 44a of the range selector 44, and the parking range (P range) is It is determined whether or not it is selected (step S12). The control unit 91 may determine whether the conditions necessary for the correction control are satisfied (step S13). The conditions necessary for the correction control include, for example, environmental conditions such as oil pressure and oil temperature, and operating conditions of the automatic transmission such as whether the gear ratio is suitable for stopping the pulley.

  When all the steps S11 to S13 are satisfied, the control unit 91 shifts to the correction control of the estimated supply flow rate Qs. On the other hand, when any one of steps S11 to S13 is not satisfied, the control unit 91 determines that the correction control is not suitable and does not perform the correction control.

  Next, the content of step S20 which is correction control of the estimated supply flow rate Qs will be described. First, when performing correction control, the control unit 91 sets a target hydraulic pressure Pt at a predetermined position of the hydraulic pressure supply mechanism 46 to a predetermined hydraulic pressure Phh (step S21). In the present embodiment, the predetermined position is the hydraulic pressure of the piston chamber 26b21 of the movable pulley half 26b2 of the driven pulley 26b. By setting the predetermined position to the piston chamber 26b21 of the driven pulley 26b, it is easy to perform correction control when the vehicle 1 stops. Further, the predetermined hydraulic pressure Phh is assumed to be a hydraulic pressure higher than the set pressure which is normally set.

  In this state, the control unit 91 switches the pump switching valve 46g to set the lubrication mode (step S22). That is, generally, since the high pressure mode is set immediately after the stop, when performing the correction control, the pump switching valve 46g is switched to set the lubrication mode once. Then, since the hydraulic oil is supplied to the main hydraulic circuit 47 only from the first oil pump 46a1, the characteristic of the first oil pump 46a1 can be grasped.

  Thereafter, the control unit 91 obtains the detected pressure Ps at the predetermined position from the DN pulley pressure sensor 82a (step S23).

  Here, the control unit 91 determines whether to increase the estimated supply flow rate Qs or to decrease the estimated supply flow rate Qs. That is, the control unit 91 has the hydraulic pressure threshold A for determining whether to increase the estimated supply flow rate Qs or to decrease the estimated supply flow rate Qs, and compares the detected pressure Ps with the threshold A (step S24). ).

  If the detected pressure Ps exceeds the threshold value A, it is judged that the supply capacity of the first oil pump 46a1 is high and there is room to increase the estimated supply flow rate Qs, and the estimated supply flow rate Qs used at the next switching time of the pump switching valve 46g Is increased (step S25). On the other hand, when the detected pressure Ps does not exceed the threshold A, the supply capacity of the first oil pump 46a1 is low, and it is judged that there is no margin for increasing the estimated supply flow rate Qs. The supply flow rate Qs is decreased (step S26).

  Next, the state of the hydraulic pressure when the above-mentioned correction control is performed will be described by exemplifying a specific case. FIG. 6 is a diagram showing changes in the target hydraulic pressure Pt and the detected pressure Ps at predetermined positions in the correction control. In FIG. 6, when the vehicle 1 is stopped, a line indicating the target hydraulic pressure Pt set by the target hydraulic pressure setting means 94 when the high pressure mode is switched to the lubrication mode, and the first oil pump 46a1 and the second oil pump 46a2 A line showing the detection pressure when the supply capacity is high as the detection pressure Ps1 is compared with a line where the detection pressure when the supply capacities of the first oil pump 46a1 and the second oil pump 46a2 are low is the detection pressure Ps2. doing.

  When the parking range is selected when the vehicle is stopped, the high pressure mode is set in preparation for an instruction from the driver such as a driving instruction. In the high pressure mode, both the first oil pump 46a1 and the second oil pump 46a2 supply hydraulic fluid to the PH control valve 46c.

  Here, when the correction control is started at time point T1, the target hydraulic pressure Pt is set to a predetermined hydraulic pressure Phh which is a hydraulic pressure higher than the hydraulic pressure which is normally set. The predetermined hydraulic pressure Phh is a high hydraulic pressure that can not be generated at the flow rate normally supplied from the first oil pump 46a1 and the second oil pump 46a2 at the time of stopping.

  In this case, the PH control valve 46c performs control to follow the target hydraulic pressure Pt. For this reason, although the detected pressure Ps (the detected pressure Ps1 and the detected pressure Ps2) does not reach the predetermined hydraulic pressure Phh, all of them are higher than the normal high pressure mode.

  Next, at time point T2, while the target hydraulic pressure Pt is set to the predetermined hydraulic pressure Phh, the lubrication mode is set. In this state, since the hydraulic oil supplied by the second oil pump 46a2 is guided to the lubricating system 46j by the pump switching valve 46g, only the hydraulic oil supplied by the first oil pump 46a1 controls the PH control valve of the main hydraulic circuit 47. It is pumped to 46c.

  In this case, the target hydraulic pressure setting means 94 sets the target hydraulic pressure Pt to a predetermined hydraulic pressure Phh which is a hydraulic pressure higher than that normally set. Here, although the PH control valve 46c performs control to follow the predetermined hydraulic pressure Phh which is the target hydraulic pressure Pt, the predetermined hydraulic pressure Phh may occur at the supply flow rate of the hydraulic oil from the first oil pump 46a1 at the time of stopping. Because there is no oil pressure, the detected pressure Ps (the detected pressure Ps1 and the detected pressure Ps2) does not reach the predetermined oil pressure Phh.

  Then, in a state where the pump switching valve 46g, the target hydraulic pressure setting means 94, and the PH control valve 46c are controlled, it is determined whether or not the detected pressure Ps exceeds the threshold A. Then, when the detected pressure Ps is the high detected pressure Ps1 exceeding the threshold A, it can be determined that the actual supply flow rate of the hydraulic oil by the first oil pump 46a1 is large and there is a margin for increasing the estimated supply flow rate Qs. . On the other hand, when the detected pressure Ps is a low detected pressure Ps2 not exceeding the threshold A, it is determined that the actual supply flow rate of hydraulic oil by the first oil pump 46a1 is small and there is no margin for increasing the estimated supply flow rate Qs. Become. Finally, at time T3, the high pressure mode is returned again, and then the correction control is ended.

  As described above, in the present embodiment, when the control unit 91 performs the correction control of the estimated supply flow rate Qs, the target hydraulic pressure Pt in the piston chamber 26b21 of the driven pulley 26b at the predetermined position is higher than the hydraulic pressure normally set. The pressure is set to a predetermined hydraulic pressure Phh and the detected pressure Ps at a predetermined position is acquired. Thereby, the maximum hydraulic pressure obtained at the predetermined position of the main hydraulic circuit 47 can be grasped. Here, if the detected pressure at the predetermined position obtained in the correction control is large (see the detected pressure Ps1 in FIG. 6), it is determined that the flow rate of the hydraulic oil supplied from the first oil pump 46a1 has a margin, A correction is made to increase the estimated supply flow rate Qs. On the other hand, if the detected pressure at the predetermined position obtained in the correction control is small (see the detected pressure Ps2 in FIG. 6), it is determined that the flow rate of the hydraulic oil supplied from the first oil pump 46a1 has no margin. A correction is made to reduce the estimated supply flow rate Qs. By correcting the estimated supply flow rate Qs of the hydraulic oil supplied from the first oil pump 46a1 in the first state as described above, a more accurate flow rate can be estimated. Then, if the lubrication mode and the high pressure mode are switched by the pump switching valve 46g based on the value of the estimated supply flow rate Qs more accurately, the lubrication mode can be increased as compared with the case where the correction control is not performed. The load on the oil pump 46a2 and the engine 10 that drives it can be reduced. As a result, fuel consumption can be improved.

  Further, in the present embodiment, when performing the correction control, the control unit 91 switches the pump switching valve 46g so as to be in the lubrication mode. As a result, the detected pressure Ps can be grasped when the flow rate supplied from the first oil pump 46a1 to the main hydraulic circuit 47 is relatively small. Then, it is possible to grasp how much the flow rate margin of the hydraulic oil supplied from the first oil pump 46a1 in the lubrication mode is, and when estimating the estimated supply flow rate Qs, the flow rate is estimated more accurately. obtain.

  Further, in the present embodiment, the hydraulic pressure supply source is configured of the first oil pump 46a1 and the second oil pump 46a2, and in the lubrication mode, hydraulic oil is supplied to the main hydraulic circuit 47 only from the first oil pump 46a1. Thereby, the characteristic of the first oil pump 46a1 used in the lubrication mode can be grasped. Further, in the lubrication mode, the second oil pump 46a2 does not supply hydraulic oil to the main hydraulic circuit 47 of high pressure, and the hydraulic oil is supplied to the sub hydraulic circuit 48 of low pressure. The load of 46a2 can be reduced. Furthermore, the load on the engine 10 that drives the second oil pump 46a2 can be reduced.

  Further, in the present embodiment, the control unit 91 performs correction control when it is determined that the rotation speed of the wheel speed sensor 81 that detects the rotation speed of the drive wheel 12 is zero. In addition, the control unit 91 performs correction control when the range selector 44 selects the parking range. As described above, if the correction control is performed after confirming that the rotation speed of the drive wheel 12 is 0 or when the instruction value of the range selector 44 is in the parking range, the correction control is performed when the vehicle is stopped. For this reason, even if the driver does not give an instruction in particular, it is possible to correct the estimated supply flow rate Qs of the hydraulic oil at a timing at which there is no problem in traveling.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, It is within the range of the claim, and the technical idea described in the specification and drawing. Variations are possible.

  In particular, in the present embodiment, whether or not the estimated supply flow rate Qs is to be increased is determined depending on whether or not the detected pressure Ps exceeds the threshold A in correction control, but the present invention is not limited thereto. For example, the value of the correction coefficient C1 to be multiplied by the reference map Ms0 may be adjusted in accordance with the magnitude of the detection pressure Ps.

1 ... vehicle 10 ... engine (internal combustion engine)
12 ... driving wheel 26 ... continuously variable transmission 26b ... driven pulley 26b 2 ... movable pulley half 26b 21 ... piston chamber (predetermined position)
28 ... forward / backward switching device 44 ... range selector (shift switching means)
44a ... range selector switch 46 ... hydraulic pressure supply mechanism 46 a1 ... first oil pump (hydraulic pressure supply source)
46a2 ... 2nd oil pump (hydraulic supply source)
46c ... PH control valve 46g ... pump switching valve (flow rate adjusting means)
46 j ... lubrication system 47 ... main hydraulic circuit 48 ... sub hydraulic circuit 50 ... crank angle sensor 81 ... wheel speed sensor (rotational speed sensor)
82 ... oil pressure sensor 82a ... DN pulley pressure sensor (oil pressure detection means)
84 ... oil temperature sensor 90 ... shift controller 91 ... control unit (control means)
92: Flow rate estimation means 92a: Storage section 92b: Correction section 94: Target hydraulic pressure setting means Phh: Predetermined hydraulic pressure Ps, Ps1, Ps2: Detection pressure Pt: Target hydraulic pressure Qs: Estimated supply flow rate

Claims (5)

An oil pressure control device for an automatic transmission, comprising: an oil pressure supply mechanism for supplying oil pressure to an automatic transmission that transmits power at a predetermined gear ratio; and control means for controlling the oil pressure supply mechanism,
The hydraulic pressure supply mechanism
Main hydraulic circuit, which requires relatively high hydraulic pressure,
Sub hydraulic circuit requiring relatively low hydraulic pressure,
An oil pressure supply source driven by an internal combustion engine to supply hydraulic oil to the main hydraulic circuit and the sub hydraulic circuit;
At least a first state in which the flow rate supplied from the hydraulic pressure supply source to the main hydraulic circuit is relatively small, and a second state in which the flow rate supplied from the hydraulic pressure supply source to the main hydraulic circuit is relatively large Flow rate adjustment means that can be switched in two stages;
Oil pressure detection means for detecting the oil pressure at a predetermined position of the main hydraulic circuit;
Target hydraulic pressure setting means for setting a target hydraulic pressure at the predetermined position;
Flow rate estimation means for estimating an estimated supply flow rate which is a flow rate of hydraulic oil supplied by the hydraulic pressure supply source in the first state;
Equipped with
The control means
When performing correction control for correcting the estimated supply flow rate, a detection pressure at the predetermined position is acquired when the target oil pressure is set to a predetermined oil pressure that is higher than the oil pressure that is normally set, and based on the detected pressure. Correcting the estimated supply flow rate,
A hydraulic control device for an automatic transmission characterized in that. The control means
2. The hydraulic control device according to claim 1, wherein the flow rate adjusting unit is switched to be in the first state when performing the correction control. The hydraulic pressure supply source comprises a first oil pump and a second oil pump.
The control means
In the first state, hydraulic oil is supplied to the main hydraulic circuit only from the first oil pump, and in the second state, hydraulic oil is supplied to the main hydraulic circuit from the first oil pump and the second oil pump. The hydraulic control device for an automatic transmission according to claim 1 or 2, characterized in that the flow rate adjusting means is controlled. The automatic transmission is mounted on a vehicle,
A rotational speed sensor for detecting the rotational speed of the drive wheel is disposed on the drive wheel of the vehicle,
The control means
The hydraulic control device for an automatic transmission according to any one of claims 1 to 3, wherein the correction control is performed when it is determined that the rotational speed acquired by the rotational speed sensor is zero. The automatic transmission has shift switching means for the driver to indicate a shift range,
The control means
The hydraulic control device for an automatic transmission according to any one of claims 1 to 4, wherein the correction control is performed when the parking range of the shift switching means is selected.